<div class="content" name="SetGain" uuid="ef932d11-7485-4661-8838-04e606f3810c"><p>The SetGain packet is transmitted from a TAPI <a href="489de77f-16d8-4c4f-939a-f795e8b42893#gt_60e0e1fa-66fe-41e1-b5e3-ceab97e53506" data-linktype="relative-path">client</a> to a TAPI <a href="489de77f-16d8-4c4f-939a-f795e8b42893#gt_434b0234-e970-4e8c-bdfa-e16a30d96703" data-linktype="relative-path">server</a> in a <a href="489de77f-16d8-4c4f-939a-f795e8b42893#gt_8a7f6700-8311-45bc-af10-82e10accd331" data-linktype="relative-path">remote procedure call</a>.
Sending this packet MUST set the gain of the microphone of the specified hookswitch
device to the specified gain level.</p><table>
 <tbody><tr>
  <th><p><br/>0</p></th>
  <th><p><br/>1</p></th>
  <th><p><br/>2</p></th>
  <th><p><br/>3</p></th>
  <th><p><br/>4</p></th>
  <th><p><br/>5</p></th>
  <th><p><br/>6</p></th>
  <th><p><br/>7</p></th>
  <th><p><br/>8</p></th>
  <th><p><br/>9</p></th>
  <th><p>1<br/>0</p></th>
  <th><p><br/>1</p></th>
  <th><p><br/>2</p></th>
  <th><p><br/>3</p></th>
  <th><p><br/>4</p></th>
  <th><p><br/>5</p></th>
  <th><p><br/>6</p></th>
  <th><p><br/>7</p></th>
  <th><p><br/>8</p></th>
  <th><p><br/>9</p></th>
  <th><p>2<br/>0</p></th>
  <th><p><br/>1</p></th>
  <th><p><br/>2</p></th>
  <th><p><br/>3</p></th>
  <th><p><br/>4</p></th>
  <th><p><br/>5</p></th>
  <th><p><br/>6</p></th>
  <th><p><br/>7</p></th>
  <th><p><br/>8</p></th>
  <th><p><br/>9</p></th>
  <th><p>3<br/>0</p></th>
  <th><p><br/>1</p></th>
 </tr>
 <tr>
  <td colspan="32">Req_Func</td>
 </tr>
 <tr>
  <td colspan="32">Reserved1</td>
 </tr>
 <tr>
  <td colspan="32">dwRequestID</td>
 </tr>
 <tr>
  <td colspan="32">hPhone</td>
 </tr>
 <tr>
  <td colspan="32">dwHookSwitchDev</td>
 </tr>
 <tr>
  <td colspan="32">dwGain</td>
 </tr>
 <tr>
  <td colspan="32">Reserved2</td>
 </tr>
 <tr>
  <td colspan="32">Reserved3</td>
 </tr>
 <tr>
  <td colspan="32">Reserved4</td>
 </tr>
 <tr>
  <td colspan="32">Reserved5</td>
 </tr>
 <tr>
  <td colspan="32">Reserved6</td>
 </tr>
 <tr>
  <td colspan="32">Reserved7</td>
 </tr>
 <tr>
  <td colspan="32">Reserved8</td>
 </tr>
 <tr>
  <td colspan="32">Reserved9</td>
 </tr>
 <tr>
  <td colspan="32">Reserved10</td>
 </tr>
</tbody></table><p><b>Req_Func (4 bytes): </b>The identifier of the
function that will be invoked on the remote server. This value MUST be set to
113.</p><dl>
<dd>
<p><b>Return Values</b></p>
</dd>
<dd>
<p>On completion of <a href="c28c36d0-579b-4e20-a100-f4e71012d5f8" data-linktype="relative-path">ClientRequest</a>, this field
MUST contain the result of the encapsulated telephony request. A nonzero
request ID value indicates that the request is in progress and will complete
asynchronously, and a <a href="b1c6fae0-09ca-4f7b-85f6-1324376d231c" data-linktype="relative-path">PHONEERR_Constants</a>
value indicates synchronous failure.</p>
</dd>
<dd>
<p>Returns a positive request identifier if the
function will be completed asynchronously or a negative error number if an
error occurs. The <i>dwParam2</i> parameter of the corresponding <a href="b0508c16-f090-4562-b367-50ea4adf8c35" data-linktype="relative-path">PHONE_REPLY</a> packet is 0 if
the function succeeds, or is a negative error number if an error occurs. If the
client specified a nonzero value in the <b>dwRequestID</b> field of the packet,
the same value MUST be used for the returned positive request identifier. The
following table lists common return values.</p>
</dd>
<dd>
<table><thead>
  <tr>
   <th>
   <p>Name</p>
   </th>
   <th>
   <p>Value</p>
   </th>
  </tr>
 </thead><tbody><tr>
  <td>PHONEERR_INVALPHONEHANDLE</td>
  <td>0x00000013</td>
 </tr><tr>
  <td>PHONEERR_RESOURCEUNAVAIL</td>
  <td>0x0000001F</td>
 </tr><tr>
  <td>PHONEERR_INVALPHONESTATE</td>
  <td>0x00000014</td>
 </tr><tr>
  <td>PHONEERR_OPERATIONFAILED</td>
  <td>0x0000001C</td>
 </tr><tr>
  <td>PHONEERR_INVALHOOKSWITCHDEV</td>
  <td>0x0000000F</td>
 </tr><tr>
  <td>PHONEERR_OPERATIONUNAVAIL</td>
  <td>0x0000001D</td>
 </tr><tr>
  <td>PHONEERR_NOMEM</td>
  <td>0x0000001A</td>
 </tr></tbody></table>
</dd></dl><p><b>Reserved1 (4 bytes): </b>An unsigned 32-bit
integer. MUST be set to zero when sent and MUST be ignored on receipt. </p><p><b>dwRequestID (4 bytes): </b>The identifier of the
asynchronous request. </p><p><b>hPhone (4 bytes): </b>An <a href="0c93f481-3429-48c5-a9e6-f0568c4cabd9" data-linktype="relative-path">HPHONE</a>. The handle to the
phone that contains the hookswitch device whose gain is to be set. This field
MUST have been obtained by sending the <a href="6b5ee45e-b5c8-4148-a9b2-b16b9b995c3f" data-linktype="relative-path">Open</a> packet.</p><p><b>dwHookSwitchDev (4 bytes): </b>The hookswitch
device whose microphone gain is to be set. This parameter MUST use one of the <a href="73925a29-5ae8-417c-baff-24db8b0aa3a6" data-linktype="relative-path">PHONEHOOKSWITCHDEV_Constants</a>.
</p><p><b>dwGain (4 bytes): </b>A DWORD-sized location that
contains the desired new gain setting of the device. This MUST be in the range
from 0x00000000 (silence) through 0x0000FFFF (maximum volume). The actual
granularity and quantization of gain settings in this range are specific to the
service provider. A value for dwGain that is out of range is clamped by TAPI to
the nearest in-range value.</p><p><b>Reserved2 (4 bytes): </b>An unsigned 32-bit
integer. This field is used for padding and MUST be ignored on receipt. It can
be any value.</p><p><b>Reserved3 (4 bytes): </b>An unsigned 32-bit
integer. This field is used for padding and MUST be ignored on receipt. It can
be any value.</p><p><b>Reserved4 (4 bytes): </b>An unsigned 32-bit
integer. This field is used for padding and MUST be ignored on receipt. It can
be any value.</p><p><b>Reserved5 (4 bytes): </b>An unsigned 32-bit
integer. This field is used for padding and MUST be ignored on receipt. It can
be any value.</p><p><b>Reserved6 (4 bytes): </b>An unsigned 32-bit
integer. This field is used for padding and MUST be ignored on receipt. It can
be any value.</p><p><b>Reserved7 (4 bytes): </b>An unsigned 32-bit
integer. This field is used for padding and MUST be ignored on receipt. It can
be any value.</p><p><b>Reserved8 (4 bytes): </b>An unsigned 32-bit
integer. This field is used for padding and MUST be ignored on receipt. It can
be any value.</p><p><b>Reserved9 (4 bytes): </b>An unsigned 32-bit
integer. This field is used for padding and MUST be ignored on receipt. It can
be any value.</p><p><b>Reserved10 (4 bytes): </b>An unsigned 32-bit
integer. This field is used for padding and MUST be ignored on receipt. It can
be any value.</p></div>